Improvement in sewing-machines



2 Sheets--S heet1.

CHARLES F. BOSWORTH.

Improvement in Sewing Machines.

Patented Jan 9, 1872.

(130 I 2 S'heats sh eet 2.

' CHARLES F. BOSWORTH.

lmprovement in Sewing Machines.

No.122,555.- Pat entedjan.9,'1872.-

% van zfyaw CHARLES F. BOSWORTH, OF MILFORD, CONNECTICUT.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 122,555, dated January9, 1872.

To all whom it may concern:

Be it known that I, CHARLES F. BOSWORTH, of Milford, in the county ofNew Haven and State of Connecticut, have invented a new Improvement inSewing-Machines; and I do hereby declare the following, when taken inconnection with the accompanying drawing and letters of reference markedthereon to be a full, clear, and exact description of the same, andwhich said drawing constitutes a part of this specification, andrepresents in- Figure 1, a front and end view; Fig. 1, a partial sideview; Fig. 2, a sectional view of the work-arm, showing the mechanismwithin the arm; Fig. 3, atop view of the mechanism,

the work-plate removed; Fig. 4, a sectional view above the work-plate;and Figs. 5 and 6, vertical sections of the needle.

This invention relates to an improvement in that class ofsewing-machines especially designed for the sewing of straw braid, orfor other purposes where it is desirable to expose a short stitch uponthe outside, the object of the invention being to make an alternatelylong and short stitch, the short stitch appearing upon one side, and thelong stitch upon the other side-such machines commonly employing twothreads, carried by an eye-pointed needle and shuttle.

This invention consists chiefly in combining a shuttle or equivalentmechanism carrying one thread with a needle carrying a second thread,when the said needle is provided with amechanism for taking andreleasing its own thread for the different stitches, as more fullyhereinafter described.

I represent the mechanism as arranged for a cylinder machinethat is tosay, a machine in which the work table is of a cylindrical form.

The needle ais arranged in the needle-bar A working in a vertical guideor head, B, to which a reciprocating movement is given in substantiallythe usual manner. The needle a, as shown enlarged in Figs. 5 and 6, ismade of tubular form down to the eye, or may be grooved to receive a rodor piston, 01, which, when raised, as in Fig. 5, opens the eye to oneside to form practically abarbedneedle, but when the piston is down, asin Fig. 6, the open side of the eye is closed, forming practically aneye-pointed needle. The piston is operated by a connecting-rod, 1),extending up through the head B, and working with the needle-bar Aprotruding through the head in the form of an arm, 0. A spring, 0,serves to force the piston down and hold it in position, closing theeye, as seen in Fig. 6. To raise the piston a cam, f, on the drivingshaft actuates a rock-shaft, G, from which an arm, 9, extends to aslide, h, operating beneath the arm 0, so that the needle-bar movingcarries with it the piston, but at. the required time the slide h risesbeneath the arm a in advance of the rising needle-bar so as to raise thepiston to open the eye. This opening occurs at the time the needlecommences to rise, and the slide h ceases its action so soon as theneedle eye has risen above the shuttle. Instead of this particularneedle and cast-off I may use any well-known needle and cast-off. D isthe shuttle working in a race, D and driven from the operative mechanismof the machine by a carrier, D in the usual manner. The needle thread isrun around a pulley, E, through a tube, H, arranged beneath theworkplate, as seen in Fig. 1, and more clearly in Figs. 2 and 3. Thistube lying directly in the line of the needle presents the thread to theneedle as it stands in its down position, and the piston being raised toopen the eye will leave the thread in the open eye; the piston closingthe eye retains the thread in that position and rises, carrying theneedle threaded up through the fabric. (This is supposing the needle tohave previously passed down through the fabric.) The fabric is then fedin the usual manner for a short stitch, and the needle again descendsthrough the fabric, carrying its own thread in the usual manner, for theeye-pointed needle. This thread is then taken by the shuttle andinterlaced with the shuttle thread in the usual manner. Were theneedle-thread tube H to remain in the posit-ion above named the needlewould again take that thread up through the work. Before the needledescends a hook or thread-holder, L, on a lever, L actuated by a cam, Lis thrown forward, and passes between the loop brought up through by theneedle, as denoted in broken lines, Fig. 4. needle entering the loop twofingers, i a, (see Fig. 4,) are arranged in such proximity to the needlethat the one, 2, throws one side of the loop back, and the other, a, theother side for- To insure the ward, as seen in Fig. 4, thus openingtheloop for the hook to enter. The thread held up by this hook L, theneedle passes down on a single branch or portion of its own thread inthe same manner as if the needle-thread were en tirely above the work,as in the usual manner. This single thread which the needle carries downis taken. by the shuttle as in other shuttle machines, and when so takenthe hook L withdraws, which gives for the passage of the shuttle theloop of thread formed by retaining theloop upon the hook as the needledescended. This operation also relieves the thread from friction ofdrawing up the stitch, drawing over the hook instead ofover the bra-id.The needle again ascends, and, were the thread-carrier H to remain inthe position first described, the needle would again take its own threadup through the fabric as before. To prevent this the thread-carrier H isarranged upon a plate, H, to which a movement is given as hereinafterdescribed before the needle rises, to take the carrier H out of the pathof the needle, as denoted in broken lines, Fig. 3; consequently, the eyeof the needle being open as before, the needle rises without its thread.The feed occurs, moving the fabric, leaving both the shuttle-thread andneedle-thread to appear upon the under side. Again the needle descends,and takes its own thread as before, and forms a stitch, no threadappearing upon the upper surface between the first and third stitch, andso continuing, each alternate stitch of a single thread appearing uponthe surface.

In straw work, for which this invention is especially designed, it isdesirable that the stitch which appears upon top should be short, whilethe under stitch is longer. To do this alternate feed of difierentlength is necessary, and this I accomplish in the following manner:

N is the feed attached to a vibrating arm I, which is actuated by a cam,K, in the usual manner for sewing-machine feeds. On a shaft, P, isarranged a stop, P against which the feed strikes to arrest its backwardmovement, as denoted in Fig. 2, it there being represented as in theposition preparatory to making the short feed. To the shaftP a movementis imparted from the mechanism of the machine at each alternate stitch,which raises the stop P, as denoted in broken lines, thus allowing thefeed to fall farther back; consequently, when the feed is thus allowedto fall farther back its next movement will be just so much longer, andthis long feed occurs while the needle is up without its thread. At thenext stitch, when the needle takes up its thread, the stop again comesdown, causing a short feed, and so continuing, long and short.

As the long feed occurs at the time that the needle-thread is notrequired, I take advantage of this fact to operate the needlethreadcarrier H, and upon the shaft 1? I arrange a cam, T, which, as thestop P is thrown down, strikes a projection, t, on the plate H andthrows the carrier into line with the needle, and when the stop isthrown up for the long feed the carrier is thrown back by a spring, S,or its equivalent.

I claim as my invention' 1. The combination of a shuttle or equivalentmechanism carrying one thread, and a hooked or barbed needle with amechanism to cause the said needle to take or release a second orneedle-thread, substantially as described.

2. In combination with the subject-matter of the first clause of claim,I claim the hook L,

substantially as and for the purpose set forth.

3. In combination with the subject-matter of the first clause of claim,I claim the hook L and fingers i n to open the loop for the insertion ofthe said hook, substantially as set forth.

4. In combination with a needle carrying its own thread and a mechanismto engage the said thread upon the reverse side of the work, I claim thehook L, arranged to operate substantially as described.

5. In combination with the subject-matter of the fourth clause of claim,I claim the fingers i n to open theloop for insertion of the said hook,substantially as set forth.

CHARLES F. BOSWORTH.

Witnesses:

A. J. TIBBITS, J. H. SHUMWAY.

